Long lasting, cost-effective solutions for water-related applications, integrating our customers’ know-how with KELLER’s H2O-expertise.

Reliable Flash Flood Alert

Dam Water Level Monitoring

Keeping Floods at Bay

Monitoring Territorial Waters

Reliable Flash Flood Alert with KELLER System

The U.S. National Weather Service records weather related fatalities, defined by the particular weather condition. In 2013, the NWS reported 82 fatalities over 21 states related to flash and river flooding. Of these 82, 45% occured in a vehicle, likely trying to cross flooded roadways.

Life-Threatening Weather Conditions

The U.S. National Weather Service records weather related fatalities, defined by the particular weather condition. In 2013, the NWS reported 82 fatalities over 21 states related to flash and river flooding. Of these 82 cases, 45% happened in a vehicle, likely trying to cross flooded roadways. In one case in a municipality in southern California, a vehicle was swept away resulting in the death of the driver. The incident occurred on a bridge, which is frequently washed over by flash flood waters during periods of heavy rain, surprising unsuspecting motorists. A subsequent lawsuit cost the city nearly $500,000 in settlement.

Inefficient Manual Solutions

At the time of the accident, city workers were tasked with driving to the roadway site to visually monitor for roadway wash over conditions. When wash over appeared imminent, a crew would erect barricades to block the roadway. However, as rain/flash flood events often occurred overnight, or at times when workers might not be available, this method proved unreliable. Unpredictable conditions made it difficult to ensure that operating procedures be strictly followed. City maintenance managers recognized that an automated solution must be implemented to reliably alert them to imminent roadway wash overs.

Flood alert by GSM

After extensive online research, city officials identified the KELLER GSM i remote data transmission unit as a possible solution. This GSM unit operates by transmitting water level or pressure data over GSM cellular networks. Level data can be collected via a variety of instruments, which provide either standard analog (4-20mA, 0-5 VDC, 0-10VDC, etc.) or digital RS485 i / SDI12 i outputs. The primary advantage of this system is the ability to send remote alerts to maintenance workers making them aware of the imminent roadway wash overs regardless of the time of day.

After consulting KELLER America, a system including the GSM and an Acculevel submersible level transmitter was specified for installation at key locations prone to flooding. KELLER America provided technical support for the setup, installation, and programming of the system, allowing the responsible city workers to receive an SMS alert indicating rising water. After the implementation, the city transitioned from manually placed, temporary barricades to permanent swinging gates, which close when flash floods occur.

KELLER could offer the National Weather Service a complete solution for the task in hand by combining a precise liquid level sensor, a remote transmission unit and customised software. A system that recognises the signs of flash floods and reports immediately. The crucial points for the National Weather Service were that the product was readily available and it delivered a simple, fast and highly reliable message via SMS.

Monitoring Dam Water Level

Water level monitoring on water dams is a basic measurement. The main requirements are the reliability (lightning protection) and very high accuracy. The 36 X W level probes can fulfil all those requirements providing added value in form of MODBUS i communication.

In Poland several hundred KELLER PAA-36 X W level probes have been installed in numerous water dams. Generally, the capillary solutions with relative pressure sensors are not acceptable, due to humidity problems. Thanks to RS485 i MODBUS communications all the absolute sensors of PAA-36 X W can easily communicate with barometric sensors also operating via MODBUS. The very strong additional lightning protection made the level probes almost "immortal" - since 2009 there has not been a single failure as it used to happen quite frequently in the past. Apart from the lack of humidity problems using the absolute sensors provide extraordinary long term stability and a total accuracy of 0,05…0,1% in real conditions.

MOSE Gate System Bids to Keep Venice Afloat

With its 175 canals and numerous waterways on its outskirts, Venice is in danger of sinking. Worsening climate change and global warming are causing sea levels to rise, bringing unusually high tides and flooding to the city. Venice has also been sinking for some years now due to the groundwater that is being pumped out from underneath its lagoon. Despite identifying the problem, it has only been possible to slow the process rather than stop it entirely. A system of gates known as MOSE has been devised to help rescue the situation.

Plagued by High Tides and Flooding

Built on a lagoon, Venice was declared a UNESCO World Heritage Site in 1987. It is spread across 118 islands and its historical districts, built mainly on marshland, are connected by a network of waterways, the most important of which is the Grand Canal.

Canal GrandeThe Grand Canal and the Rialto Bridge


High tides and flooding are the city’s constant enemies, with escalating climate change leaving no hope of relief. Increasingly, Venice is also combatting subsidence as its sandy subsoil sinks by a few millimetres every year. Go back 100 years and it lay around 25 centimetres higher out of the water than it does today. When its industries moved to the outskirts of the city in the 1960s, there was a great need for fresh water, so groundwater was simply pumped out from under the lagoon. However, this too is now causing Venice to sink. Although the problem was identified in the 1960s, restricting the volume of water being pumped could not stop the process entirely.

Residents are alerted when the sea level rises too high, enabling them to prepare for the impending “acqua alta” (“high water”). However, sandbagged doorways, wooden walkways and water pumps are not a long-term solution for saving the city. Rising water levels are particularly common in Venice in autumn and winter, with the number of floods having doubled over the past 40 years.


Greenhouse Effect and Rising Sea Levels

The man-made greenhouse effect causes the atmosphere to heat up, with consequences including the melting of the world’s glaciers. In Greenland, for example, scientists have observed significant losses in the ice shelf and have calculated that more ice melts in summer than is able to form in winter. The resulting increase in sea levels is threatening low-lying countries.


Anstieg des Meeresspiegels

Rise in the sea level


A Gate System to Ward Off the Adriatic

A system of gates has now been devised to keep the Adriatic Sea away from the city. In 2001, the Italian government voted to instigate the MOSE (“Modulo Sperimentale Elettromeccanico”, or “Electromechanical Experimental Module”) flood prevention project, which uses steel gates to hold back high tides at the three entrances to the Venetian Lagoon. Secured by concrete piles, the gates are 20 metres wide, 5 metres thick and up to 30 metres high. When there is a danger of high tides, air is pumped into the gates, which rise to form a protective barrier and block off the lagoon like a floodwall. When the water is at a normal level, the gates lie submerged beneath it. The project envisages 79 of these steel gates covering a total length of 1.5 kilometres.

SenkkastenConcrete piles/Caissons


MO.S.E SchleusensystemThe MOSE gate system


KELLER Transmitters in the Concrete Piles

The customer built digital (bus) profilometers that use KELLER’s high-precision series 33X and 35X transmitters with IP68 protection. The profilometers have been installed in the concrete piles and monitor the structure of the caissons.

This solution guarantees extreme precision – down to one-hundredth of a millimetre over a length of several kilometres – and represents a major advance in quality compared to the technologies used to date in similar applications.

Surveillance of Russia’s Territorial Waters

The Federal Service for Hydrometeorology and Environmental Monitoring of Russia "Roshydromet" monitors, among others, surface water levels and temperature in rivers and other territorial waters. In six of its regional departments the organization has started to use autonomous hydrological systems, which comprise of KELLER hydrostatic pressure (level) and temperature probes and GSM i modules for automatic data registration and transfer.

Six of the organization’s regional departments are using autonomous hydrological systems comprising of KELLER PAA-36 X W hydrostatic level probes as well as GSM-2\GSM-2 BOX modules for automatic data registration and transfer.

Hydrometeorology monitoringClosed territory of a meteorological station on the coast of the Barents Sea

hydrological systemInstalled GSM-2

Monitoring Surface Water Levels

Two of the six departments are using KELLER systems in the Gulf of Finland, open to the Baltic Sea and on the Barents Sea, open to the Arctic Ocean, where the air temperature can drop to -35 °С. The systems have been collecting and sending data once per hour without the necessity to change batteries for more than a year.

Two of twelve KELLER systems are being used at the department’s test site in the Novgorod region as well as in the Far East, connected to a GSM-2 rain catcher.

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